How to Determine if a Hot Runner Sensor Has Zero-Point Drift

It only requires a quick two-step process that is easy to use and doesn't require any specialist equipment. Here's how:

Step 1: After thermal stabilization, measure the zero-pressure output.

To give the sensor time to stabilize, heat the hot runner to the standard production temperature and hold it there for half an hour. After that, fully depressurize, release the runner pressure, and wait ten minutes for the output to stabilize. Note the value of the sensor's current output.

Step 2: Determine Deviation by Comparing with Standard Value

A hot runner sensor's standard zero-pressure output is typically 4mA (current output type; most models with integrated amplifiers utilize this standard):

Output deviation ≤ 0.02mA: No zero-point drift, typical variation;

There is a small zero-point drift between 0.02mA and 0.2mA, or 0.1%FS and 0.5%FS;

Deviation > 0.2mA, or > 0.5%FS, indicates severe zero-point drift, which is typically brought on by age.

The zero-voltage standard output for voltage output type sensors is typically 0V. The judgment logic is identical to that of sensors of the current type. Zero-point drift is present if the divergence is more than 0.01V.